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Poor Quality EHS Studies

EHS is one of the areas where alarmists have been most active. A growing number of web sites, lobbyists, and even scientists are promoting this issue. They claim to be fighting for the rights of the electrosensitive. There are also a growing number of web sites and consultants that are taking advantage of the situation to sell a wide range of quack remedies to the gullible. Despite the overwhelming negative evidence from well conducted double blind studies and the negative conclusions of virtually every public health organization starting with the WHO, the EHS lobby points to studies that back up their claims.

In its report of Jan. 2009 "Health Effects of Exposure to EMF" the SCENIHR scientific advisory committee to the European Commission had this to say about EHS (P. 35).
"In the previous opinion, it was concluded that scientific studies had failed to provide support for a relationship between RF exposure and self reported symptoms. Although an association between RF exposure and single symptoms was indicated in some new studies, taken together, there is a lack of consistency in the findings. Therefore, the conclusion that scientific studies have failed to provide support for an effect of RF fields on self-reported symptoms still holds. Scientific studies have indicated that a nocebo effect (an adverse non-specific effect that is caused by expectation or belief that something is harmful) may play a role in symptom formation. As in the previous opinion, there is no evidence supporting that individuals, including those attributing symptoms to RF exposure, are able to detect RF fields. There is some evidence that RF fields can influence EEG patterns and sleep in humans. However, the health relevance is uncertain and mechanistic explanation is lacking. Further investigation of these effects is needed. Other studies on functions/aspects of the nervous system, such as cognitive functions, sensory functions, structural stability, and cellular responses show no or no consistent effects."

In this section we will do a proper scientific analysis of some of the "studies" promoted by the EHS lobby and show their fatal flaws. Real science requires experimental results that are objective and repeatable. Anecdotes or stories about an individual's personal "experiences" and "testimonials" are not considered science. In science and medicine, the "gold standard" is a randomized double blind trial. A patient's symptoms will either improve or not improve compared with a placebo in a double blind trial. This is a trial in which neither the experimenter nor the subject knows whether the "real" or "placebo" treatment is being administered. Note that scientists agree that there is such a thing as the "placebo effect". Subjects often report improvement if they believe something is being done for their condition - even if it's just a sugar pill. For a new treatment to be considered worthwhile, it must be better than placebo. In the case of EHS, a subject - who is often people who claims to suffer from EHS, is alternately exposed to real EMF such as a cell phone, or Wifi device etc and then "sham" EMF in which the device is off. Neither the subject nor the experimenter knows which is which until after the trial. This straightforward experimental protocol does not require any understanding whatsoever of the underlying cause of EHS - if it exists.

Every single properly conducted double blind trial of EHS to date, has failed to show a significant effect of EMF on health. See our EHS page for more information on these studies. There have been approximately 40 such studies to date. Let us now review a few of the actual studies that alarmists use to back up their claims.

Effects of Cell Tower Signals on Self Reported Symptoms

The following paper is a "study" of the effects of GSM wireless signals (cell tower EMF) on self reported symptoms (EHS) and sleep. The study was published on Piers Online Vol. 2 No. 7 2007. The study group consisted of 36 women and 35 men. A bit over half the subjects entered the study as self declared "electrosensitives". A double blind experimental protocol was used. Data was collected on EHS symptoms, including headache, cognitive function, mood, and electroencephalographic recordings (for sleep patterns).

The author's conclusion: "The study indicates that during laboratory exposure to 884MHz wireless signals, components of sleep, believed to be important for recovery from daily wear and tear, are adversely affected. Moreover, participants that otherwise have no self-reported symptoms related to mobile phone use, appear to have more headaches during actual radiofrequency exposure as compared to sham exposure. However, subjects were not able to detect the true exposure status more often than would have been expected by statistical chance alone."

But what are these conclusions based on? From the body of the study we learn that to reach stage 3 (deep) sleep, it took an average of 6 minutes (0.1 hours) longer with real vs. sham EMF, and that stage 4 sleep was decreased by 8 minutes!! Also the group that experienced slightly more headaches was the "normal" group not the electrosensitives!! Neither group could guess better than chance if the EMF was on or off!!

This study suffers from several flaws. Of all the symptoms being measured, it reports the results only of those where an increase in symptoms was measured (headache, sleep). It omits results for the other symptoms - which might show an improvement. The size of the measured effects on sleep is small as is the number of subjects. The headache result affects the "wrong" group and the size of the effect is not given. These "results" are almost certainly due only to chance.


EHS Symptoms near Cell Towers

The following is a critique of a pair of studies done in France of people living near a cell phone tower and self reported EHF symptoms.
 
Paper # 1 Title: Investigation on the health of people living near mobile telephone relay stations: I/Incidence according to distance and sex
Paper #2 Title: Symptoms experienced by people in vicinity of base stations: II/ Incidences of age, duration of exposure, location of subjects in relation to the antennas and other electromagnetic factors

The study used questionnaires that were sent to 530 people. They responded to questions to evaluate the following subjective symptoms: tiredness, headache, sleep disturbance, discomfort, irritability, depression, loss of memory, dizziness, and libido decrease. These symptoms were correlated with distance from the cell tower. The studies found that self reported symptoms varied according to distance from the towers. Based on their findings, the authors recommend that the minimal distance of people from cellular phone base stations should not be less than 300 m.

The biggest problem with these French studies is that no actual measurements of EMF exposure were made. Subjects were aware of their distance from the cell tower, and their subjective symptoms might just be due to this awareness and not actually due to the EMF. The final results of the largest study of this type to date involving 3526 subjects have just been published (Feb. 2009). In this German study actual EMF exposure measurements were made for each subject. No correlation between EHS symptoms and the level of EMF exposure was found for any class of subjects - including those who had declared themselves as electrosensitive. This German study - by far the largest and most rigorous to date - convincingly negates the French study and shows that EHS symptoms are neither caused by cell towers nor several other common sources of EMF. See more details on this German study on the cell towers page.


Dr. Magda Havas of Trent University is probably Canada's leading alarmist. She has a web site that promotes her alarmist views. Following are a few of examples of her deeply flawed "studies" on the effect of EHS.
More Flawed EHS Studies:   Havas & High School     Havas on WiFi in San Francisco
Check out our page on EHS Product Scams

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